Measuring Cognitive Effort with Pupillary Activity and Fixational Eye Movements When Reading: Longitudinal Comparison of Children With and Without Primary Music Education

This article evaluates the Low/High Index of Pupillary Activity (LHIPA), a measure of cognitive effort based on pupil response, in the context of reading. At the beginning of 2nd and 3rd grade, 107 children (8-9 y.o.) from music and general primary school were asked to read 40 sentences with keywords differing in length and frequency while their eye movements were recorded. Sentences with low frequency or long keywords received more attention than sentences with high frequent or short keywords. The word frequency and length effects were more pronounced in younger children. At the 2nd grade, music children dwelt less on sentences with short frequent keywords than on sentences with long frequent keywords. As expected LHIPA decreased over sentences with low frequency short keywords suggesting more cognitive effort at earlier stages of reading ability. This finding shows the utility of LHIPA as a measure of cognitive effort in education.